The Democrats hoped/boasted that they would win the 2012 presidential election because Paul Ryan and the Republicans had passed a budget that reformed entitlements and federal taxes. Democrats have neither passed through the Senate or even written down a budget that does either.

But the theory was that the Ryan plan that reforms Medicare so it does not go bankrupt in the coming years could be attacked as anti-Medicare. This was made difficult by the fact that the Ryan plan does not make any changes for Americans over the age of 55 while Obamacare makes several damaging changes to fund itself at the expense of Medicare and through rationing.

If the Democrat theory held water we would have seen Ryan on the defensive. At best the Democrats got a draw on their "silver bullet" issue that wasn't.

I gave the laurel decisively to Paul Ryan. The GOP challenger was positive and substantive, displaying a foreign policy depth and command that challenged the vice president in his area of presumed expertise.

Ryan offered a clear vision and substantive agenda for the next four years, coupled with a willingness to tackle difficult entitlement reforms. I thought Ryan did a solid job of fending off predictable Mediscare and tax attacks, while maintaining his composure and message discipline. Most objective voters watching this performance will conclude that Paul Ryan has the stature and command to lead the country- and understands their needs and concerns.

Watching the debate with 60 college students at a local campus,and gaging their reaction, I found Joe Biden's debate performance uneven and his demeanor- with alternating mirth and grumpiness- a distraction. Biden's energy and aggression was undoubtedly a crowd pleaser for partisans, but did little to persuade swing voters.

The effect of this debate will be limited, with no decisive gaffes on either side. However, Paul Ryan the challenger went head to head with the Vice President and came out on top, in the process mooting the attacks of Team Obama.

Karen FloydFormer South Carolina Republican Party chairwoman; CEO, The Palladian Group :

The benchmark for measuring the vice presidential debate winner is which candidate excelled in his ability to connect with and energize his targeted audience. While Vice President Biden successfully communicated to the Democratic base, so too was Congressman Ryan formidable in his ability to appeal to the undecided, independent voter.

Vice President Biden clearly rejuvenated the spirits of the Democratic base, after last week's letdown by his forceful and sometimes "bullyish" demeanor. Congressman Ryan also secured his credibility with the independents by his composure, discipline and grasp of complex issues.

The contrast, not just ideological, but in style, was stark. At the end of the day, both men effectively mastered the task at hand.

There is no disputing the fact, however, that Congressman Ryan was the most vice presidential.

It was clear that the Obama-Biden game plan is to lie to the American people because they do not have the facts on their side. We all know that President Obama failed miserably last week, and what Joe Biden displayed tonight is what liberals love to do...whine. When all the debating is done this country is still in despair because of the failed policies of the last four years.

For me, the funny thing was that Paul Ryan more than held his own on a perceived weakness - foreign policy - while Joe Biden largely dominated the budget and tax issues, which was supposed to be Ryan's forte. As far as these things go, it was a helluva debate, but Biden did what he needed to do. He was succinct, direct and to the point. He won.

Paul Ryan was intelligent and clear. Then wisely and politely got out of Joe Biden's way so that Joe Biden had plenty of room to be a jerk. The strategy worked beautifully. Joe Biden was, indeed, a jerk.

Vice presidential debates are normally a sideshow, but Thursday night’s faceoff between Paul Ryan and Joe Biden commanded unusual attention, and not just because the race had tightened after President Obama’s weak performance in last week’s first presidential debate.

Certainly partisans on either side tuned in to see whether Biden would slow down Mitt Romney’s momentum, or whether Ryan would put more wind in his ticket’s sails. But the dynamic that made the debate such compelling political theater owed primarily to Romney’s pivot toward the center in the first debate and who Paul Ryan is.

Romney’s pivot seemed to catch President Obama off guard. But it shouldn’t have. It’s axiomatic in presidential politics that candidates appeal to their base in the primaries and move toward the center as the general election nears. Obama himself did that in 2008, when in the three or four weeks after he clinched the Democratic nomination he issued almost daily statements moderating his views.

The difference for Romney this year was that the bitter Republican primaries, where his conservative credentials were routinely questioned, prevented him from pivoting sooner. Any deviation from strictly constructed conservative views earlier in the general election campaign would have confirmed the worst fears of GOP voters and cost Romney his base. A course correction was only possible when his campaign seemed headed for the rocks, because it could be countenanced by Romney’s conservative doubters as doing what he had to do to win.

So when Romney departed from conservative fiscal orthodoxy – by pledging, for instance, that rate reductions would result in no net tax cut – it put Ryan’s reputation as the intellectual architect of fiscal conservatism into the debate spotlight. Would the Democrats be able to use Ryan to call Romney on his move to the center?

Biden certainly tried to do that Thursday night, but Ryan gave as good as he got, defending a conservative fiscal approach, and in the immediate aftermath of the debate Round 2 was widely viewed as a draw.

We’ll know more with the next round of polling.

But one thing is already clear from the movement after the first presidential debate: The persuadable voters on whom the election’s outcome rests are looking for centrist solutions to the nation’s problems. In that sense, they have already arrived where the winning candidate will need to land.

Because in the end, whether Romney or Obama prevails, the next president will have to renege on some of his promises and go along with a compromise fiscal plan to reduce the deficit by cutting spending and raising taxes, along the lines recommended by the Simpson-Bowles commission. The central issue for voters in the middle is who seems more legitimately able to make that move.

To make an impact on the election Biden had to trounce Ryan. That did not come close to happening.

Remember, the only voters left in play are the undecided and those of weak political loyalty. How would such voters react to tonight's debate? In Ryan they saw someone who is sober and substantive, and in Biden they saw someone who was disrespectful, snide, constantly interrupting, and laughing and smiling at inappropriate times and topics. Indeed, Biden came across as almost bipolar, hardly able to contain himself for the first 60 minutes of the debate, and then very low energy and reserved for the final 30 minutes.

My guess is that voters who are still in play value style over substance, and in the style category, Ryan trounced Biden. Undecided voters in heartland swing states do not like the constant rudeness and disrespect Biden showed toward Ryan.

Here's what's important: The American people already know Biden and Obama. And they know they have a terrible track record. When they meet the alternative in a debate, and they find that alternative to be credible and to project confidence and leadership, they are likely to go with the alternative. That's what happened dramatically in the first presidential debate, and I think some more of that probably happened tonight.

And if Obama comes out in the second presidential debate all combative and aggressive, as he is probably being coached to do, it will backfire on him and seal the failure of his re-election campaign.

In the meantime, Biden throwing the State Department under the bus tonight will have immediate consequences. There are career people at State who will cut the Obama administration's legs out from under them on this.

Jim PapaSenior Vice President and Managing Director, Strategy and Operations, Global Strategy Group; former Special Assistant to President Obama for Legislative Affairs :

The vice president gave a very strong performance. In every answer, he showed more depth of feeling and greater command of the subject matter than Ryan did. He was also very quick on his feet, delivering memorable lines off the cuff.

Ryan gave a serviceable performance, but not an outstanding one. He suffered from a stature gap -- he looked like a graduate student defending his thesis. His most polished answers also felt the most rehearsed.

To the undecided voter, Biden communicated abiding commitment to the middle class and drilled down on Romney/Ryan weaknesses (e.g. Afghanistan). Along the way, he re-energized Democrats. The Obama campaign couldn't ask for anything more, which is why the Romney campaign is trying to talk about Biden's smiles and interruptions. Of course, they didn't seem to mind when Romney smiled and interrupted during the last debate...

I have no confidence in predicting how the debate might affect the dispositions of the sliver of the electorate that has managed somehow to stay undecided.

What I am certain of is that Biden's performance will help revive Democratic interest and enthusiasm in their ticket and diminish any further shift in support to Romney. Biden did what Democrats wanted Obama to do in the first debate. Biden wins on both style/presentation and the strength and truth value of his arguments with Ryan. Now the responsibility shifts once again to the president. But I suspect he will gain a modest lead before the second debate.

The debate was much more dynamic and informative than the first presidential debate between Barack Obama and Mitt Romney. That said, I believe Ryan was head and shoulders better than Joe Biden - both in style and in substance.

Though I am fairly certain both candidates accomplished the goals of their respective parties - Ryan, staying articulate and and continuing Romney's momentum; Biden, playing it strong and feisty in order to energize Democrats - and brought home a win.

However, it's hard to imagine what Biden was thinking with the constant grinning and laughing throughout Ryan's discussion of serious subjects. His smugness was extremely off-putting and far from what I'd expect of my country's vice president. I doubt he won over many in the heartland or southern swing states with his behavior tonight.

Slow Joe Biden came across as old, angry, smirky, disrespectful, and hoarse while Paul Ryan was unflappable, calm, thoroughly knowledgeable, and likable.

Biden went on too long and seemed at times to be shouting. The first big mistake Barack Obama made even before the stimulus and socialized medicine was tapping a mediocre, long-winded senator to be his vice president. Mitt Romney is much better at hiring a vice president than was Obama and a big part of the job of serving as president is hiring good people to work for you.

Ryan accomplished his goal of doing no harm, getting in a few zingers and buttressing the Republican arguments for limited government, reduced spending and entitlement reform. But Biden accomplished his as well. He argued forcefully for the Democratic way. He fired up the base. He made the case for President Obama’s policies far better than the president himself.

And what happened in Danville will largely stay in Danville. It’s lasting effects will be to erase Al Gore from the record book as “most exasperated debater ever” and to set up what should be two enormous clashes between the presidential candidates next week and the week after.

There are, however, still voters to be convinced … particularly in battleground states. The presidential candidate who best connects with them from this point on is the one who will be celebrating after Nov. 6.

I am embarrassed that the vice president of my country acted like a hee-hawing, rude, obnoxious bully.

The Democrats are celebrating that he was passionate and fed red meat to them, but I heard nothing of substance. Paul Ryan was right on when he kept talking about how when you don’t have a positive record to run on, you demonize your opponent.

Ryan remained calm, composed, and respectful even when being repeatedly interrupted and laughed at.

Every Republican should be insulted by Biden’s attitude and demeanor. But I suspect that it did not play well with independent voters. People who watched this wanted facts and figures and to have a substantive debate. What they got was a sitting vice president laughing during discussions on Medicare, Iran, veterans, the economy and health care.

I also think the next few days will show that Biden was either lying about what the White House knew about Benghazi or that the State Department and White House are totally inept.

Biden's job in this debate was far different from his imperative in the debate against Sarah Palin four years ago.

In 2008, he had to avoid appearing patronizing or disrespectful to the first woman on a GOP ticket. He largely accomplished that, while allowing Palin's winky superficiality to show through. In this debate, it was essential that he be engaged and aggressive after Obama sleepwalked his way through the first debate and allowed Romney back into the game. And he largely accomplished that, giving Ryan no quarter and vividly calling out his misstatements and hypocrisies. Biden's mission was not to be Mr. Congeniality, but to show Obama how to show some spine, and to reassure Democrats that their ticket wasn't going to roll over for the extreme self-makeovers that Romney and Ryan are trying to get away.

While he may have been over the top at times, Biden did what he came to do.

Four different Bidens showed up for tonight’s debate. First, the Biden who smiled and laughed at forced and inopportune moments; second, the Biden who repeatedly interrupted; third, the Biden who became heated and angry; and fourth, the Biden who was quiet and reflective. Watching Biden’s performance was a bit like watching Showtime’s “United States of Tara.”

Despite all of that, Mr. Biden won the night. He was simply more effective at controlling the debate, challenging his opponent’s premises, and delivering memorable messages. Even more importantly, he forged a warmer and more emotional personal connection with viewers, particularly when addressing seniors regarding Medicare.

Although Mr. Ryan had some good moments, his lines too often came across as overly rehearsed. His tone - while more even than Mr. Biden’s - was flat. Slowing down the tempo of an accelerating debate can be an effective tactic - but it wasn’t tonight, and Ryan failed to adjust. As a result, most of the conversation about tonight’s debate, good and bad, will center on Mr. Biden. Ryan’s performance will likely be completely forgotten by next week.

Joe Biden won the debate, with his best arguments honed less by moot court prep than by real-life policy arguments in the Situation Room and the Oval Office. Here is a vice president confident in arguing with the president and other key leaders about the major choices America faces at home and abroad. That experience paid off against Paul Ryan, who seemed unprepared for a happy warrior and outmatched by a seasoned professional.

Biden defended the 47 percent (including his parents), the job-creating stimulus, the Medicare guarantee, Social Security, and the middle class. Biden revealed the hollow math of the Romney Ryan budget and breathed new life into some Democrats who were dismayed by tightening polls last week. Biden will rally the base and those undecided center-left voters still deciding whether to vote. In contrast, Paul Ryan came in billed as budget king - and then his math didn't add up. Advantage Obama. You can't beat something with nothing - and Ryan brought only vague promises that Romney would write a bill with Democrats.

Paul Ryan had the tougher job - Biden had to be aggressive in advancing Obama policies he helped shape - and he was - while Romney has run away from Ryan's budget, Medicare and abortion views. But Ryan need not despair - he will have a chance to run on his own un-Etch-A-Sketched views in 26 days - after Obama-Biden wins and a race for the 2016 nomination begins.

Yes, that light you see at the end of the 2012 campaign tunnel is the oncoming 2016 train which both Biden and Ryan may have caught tonight.

Dante ScalaAssociate professor of political science, University of New Hampshire :

A lot will be made of Biden's behavior during the second half-hour of the debate, when he repeatedly interrupted Paul Ryan during their discussion of domestic policy. But Biden was most effective, I thought, in the first half hour, when he stood his ground on the administration's foreign policy accomplishments, calmly but firmly.

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